Continuity isn't a monolithic feature of the new operating systems so much as it is a range of features, each with its own hardware requirements and mode of operation. As we already did for iOS 8's Extensions, in this article we'll be using Apple's developer documentation, WWDC videos, and early reports from forums and rumor sites to explain the technology behind these features. We'll speak in brief about how phone integration and AirDrop work. Then, we'll examine how Handoff works and how developers can integrate Handoff support into their own iOS and OS X applications.